Intake/exhaust combo suggestions
 

I have a 2012 G37s sedan and right now the only breathing mod it has is the exhaust. When I bought the car it was already installed. It's a Hallbuilt Y-back 3" single exit with a 4.5" tip.

I was thinking of picking up a Stillen dual catback, FA RHFC and probably a Z1 intake (I don't really want to shave away the radiator brace and the z1 doesn't require trimming). I'm not sure I'll do much more than this performance-wise, at least for a while. I'm not really looking to get the most of the most performance. I'm more looking to build in a bit of a hybrid path of visuals/sound and performance.

I live somewhere where I don't need to pass inspections but I just don't want the car to be really loud and obnoxious. I would prefer it would drop in decibels from what it is now.

I'm concerned getting an HFC and the Stillen dual catback is going to make it louder when one of my goals is to make it quieter. Obviously I'll get a bit of noise from the intake but what I really want is to be able to cold start the car in the garage without it rumbling through my house and a sound closer to stock. I'm okay with it making some noise when I step on it but in general I'd like it a little more tame.

How does this combo sound for my goals? Are there any better suggestions out there?

Keep the stock intakes
they flow great and are the quietest by design
Aftermarket intakes don't concern themselves with noise.
and unless you run a mesh grill, there will be no visual cue

Best way to keep the exhaust side quiet...
Keep the cats or go turbo lol
An exhaust with inline AND Hemholtz resonators will help keep the drone at bay

Going to a Stillen, Invidia or even a Top Speed exhaust will make it quieter compared to the 3" single you got. OEM cats keeps the sound suppressed best, so moving to a HFC will make it louder. But if you want to go HFC, your choice in FI RHFC is for sure the best.

Does you HBP 3" have a resonator or only the helmholtz chamber? I just got my exhaust from him recently

keeping the stock air box with K&N filter is the simplest. But the Long tube setup looks good to me when I see the bay. Takeda is another unit that doesn't require cutting but Z1 is better.

Your 3" Hallbuilt will be louder than Stillen, hands down. I'd go full Fast Intentions. I personally don't like when exhaust parts are mixed and matched. Hence why I have full Motordyne but it's too loud for what you want.

Aftermarket intakes will give you more noise under WOT. Z1's intake is decent but it's just too much damn silicone. I personally will be going with SOHO Motorsports intake but you said no trimming so that's not an option. Plus it requires a tune or re-tune in my case. I would avoid any intake where it's silicone going through the radiator support, just my .02 cents.

"Go turbo" - Now that's funny SkysG37.

Aftermarket intakes don't make much noise until you're under load.

Replacing your OEM cats will certainly cause your garage walls to rumble while the car is warming up, and afterwards for that matter. If that's unacceptable, then pass on the aftermarket cats.

Thanks. I'm not sure if it's resonated or about a chamber, actually. It came with the car; I didn't order from him. I just know the details because I asked him and he told me.

I do also like the look of the long tubes and it's part of the reason I want an intake. If I end up being okay with cutting away the car, I'd probably try an admintuning intake.

I considered K&N filters but I think I'd rather wait and replace the intakes entirely.

Is that an OCD thing? Because it kinda bugs me in that regard too. I just saw a video of this setup and liked how it sounded and there seems to be limited information on the sounds of setups and no real comparison because nobody is A/B-ing these.
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They're all spread across different videos so we have no way of knowing how they sound in relation to each other or how relatively loud they are (besides asking people here who have experience).

I also sort of don't like the silicone but I'm trying not to do irreversible changes to my car incase i want to sell it (or very difficult to reverse). Maybe I'll change my mind on that...

Thanks. Right now I think the exhaust alone is causing all the noise as the sound bounces off the garage door (till i open it) and even after it's open it's pretty loud.

So even switching to a quieter exhaust, adding an HFC would net higher noise levels during start/warm up?

It will help if the cats you target are themselves resonated. But basically, yes, aftermarket cats will be louder than otherwise, regardless of your catback. The most quiet catback would be OEM.

And if you're thinking long-tube headers... Yikes! That will be crazy loud.

AdminTuning intakes are silicone through the radiator support and will also require trimming along with a tune. Another great option is the Upton 3" Intakes from Mike Upton, very popular with the Z guys. I've chatted with him on IG, nice guy and makes IMO one of the better if not best 3" intakes. Trimming and tune required but these are solid piping through radiator support, the MAF sensor is located underneath for stealth look, and upgrade options available:
Upgrade Options:
-velocity stacks with bigger filters
-gold heat reflective tape, painting, powder coating
-PCV delete kit
-Throttle body coolant delete kit
-Coupler color choice of black, blue, red

If I change my mind and go 3" intakes, I'll be going Upton. Here's a link but best way to learn more and get the best price is through his IG, upton_mike. https://allianceracing.com/products/...coupe-or-sedan

Stillen Gen 3 Intakes are solid through the radiator and do not require a tune.

As for the exhaust, yes that is partly OCD but also partly me having been a member/owner for 6 years and hearing so many different setups online/in person.

Very interesting.. will consider this. Thanks.

I’ve had Michael’s kit before. For the price, you can’t beat it. And it’s nice to support the grassroots type folks.

only annoying thing with 3” is the moment you install it, you need a tuner to send you a base map with the MAF scales or install it with your tuner.

Hallbuilt
 

You think you’ll get rid of the Hallbuilt set up you have right now? I would like to hear it and maybe buy if you plan on selling it.

Yes but not yet because I have a few more things I need to buy unrelated to the G before I start making changes.

See my Instagram for exhaust sounds and let me know if you need other videos. I don't have a camera to mount by the way. It's @AnotherVQ

I'm preparing to purchase a replacement exhaust and I wanted to clarify I'm okay with noise, I just want it to be overall a little quieter than my current setup. My main concern is really the cold starts. I don't like how noisy it is when I start it at home.

Here's a picture of the current exhaust... Took it at night so it's not the best but it should be enough to see a good amount.

https://cimg2.ibsrv.net/gimg/www.myg...d57338e90a.jpg

I was getting a quote on some work at a shop and took some pictures while they had it lifted. The guy looking underneath commented on the welding job on the hallbuilt.. stating that it was a really good job.

https://cimg2.ibsrv.net/gimg/www.myg...c39e52bb51.jpg
https://cimg9.ibsrv.net/gimg/www.myg...0ea32d97e3.jpg
https://cimg0.ibsrv.net/gimg/www.myg...e62777022b.jpg
https://cimg4.ibsrv.net/gimg/www.myg...90701b31bb.jpg


I'm going to have shops install my stuff as I don't have the room and would need to buy all kinds of tools, some very expensive, to do this myself and don't intend on switching it once installed..

I have a shop in town who quoted me $300 for catback + high flow cats and it would take them 2 hours. They quoted $150 to install a cold air intake that requires cutting in the front and would take another two hours They would drop me off at home since I'm pretty close. I'm not too sure how I feel about their shop, though.

They told me on Friday to come in today (Memorial Day) and they'd be open and give me a quote on the work. I got there first and they helped some lady who came after me first. I heard them tell her they weren't even open today and were just cleaning the shop floor. I was waiting at least 30 minutes before they helped me and it's not like they were busy. The guy tried to lift my car by chassis first and it started wobbling when he'd raise it so he put it back down and put the car onto a lift you drive onto that lifts by the wheels. They got my door sill dirty and my door. I think they made my pedals slippery.. I have no way of knowing if that was my shoes or not.. I was assuming it was until I realized how dirty they made my car.

A shop 40 miles away from me quoted "$25 per section" meaning each joint and for cats he said he has to see it and if it bolts up by the motor it's a different price but if it's in-line it's $80 and if it's just bolted on it's $25 per side. He confused me a bit and I tried to get clarification but he just worded things weird so that's the best breakdown I could get.

Other places have garbage ratings or won't work on the cats because they just say they don't want to do that on this car. There's one more place, the main place I wanted to go. I can never get them to answer the phone. I spoke to some lady at a shop that I thought was an auto shop but it's more of a place that sells exhausts and she reccomended them after I had already been trying to contact them. She told me they are still in business though. That night, they replied to the message I sent on FB saying they'd be open Tuesday the 26th. So I'm still waiting on a quote from them. They have really good reviews and are 34 miles away from me.

Your diff bushing is out. Need to fix that.